BioTraces Inc. (BT Inc.) has developed an ultrasensitive quantitation system which can be used with a large family of isotopes. This system supports label multiplexing; many co-resident isotopes in the family can be quantitated simultaneously, allowing either the pooling of labeled samples or the pooling of distinctly labeled probe reagents for multiple targets. The proposed research will add two dimensional (2D) spatial resolution to the capabilities of the system, in support of nucleic acid quantitation and fractionation, including sequencing. Because of the extensive multiplexing capabilities and superior sensitivity, the proposed technique will greatly increase sample throughput in fractionation/quantitation tasks.